1. Field of the Invention
This invention relates to a removable lid for a cup and, more particularly, to a lid assembly which is used to form the lid. The lid of the present invention is especially suited for disposable coffee cups and drinking cups. The lid assembly of the present invention avoids inadvertent splashing which occurs due to movement of the cup.
2. Art Related to the Invention
Splash-proof lids for drinking cups are known. Typically, they comprise a round, removable cover which fits tightly over the top opening of a cup to prevent unwanted spillage of the contents of the cup while allowing the user to drink the contents of the cup even though the lid remains on the cup. To allow the user to drink the contents of the cup while the lid remains on the cup, both a drinking hole and an air hole are provided in the lid. Both holes are configured to prevent unwanted loss or spillage of the contents of the cup which occurs when the cup is unintentionally moved. Typically, such lids are used on disposable cups which the user takes on a train, a plane, in a boat, or in a car.
The drinking hole is usually positioned at the edge of the lid next to the side wall of the cup, while the air hole is positioned either centrally in the lid or along the edge of the lid next to the side wall of the cup, opposite the drinking hole.
One of the problems in the prior art is that various lid assemblies tend not to be completely splash-proof. There is a need to invent a cup which is simple in design but yet splash-proof. Furthermore, there is a need to provide a simple design which can be employed with disposable cups.
A simple lid assembly for making a splash-proof lid for a cup has now been discovered. The lid is intended to be disposable and for use with disposable drinking cups such as the type used for coffee, tea, etc. The lid has an air hole which is centrally located in the lid and a drinking hole which is located along the periphery of the lid. The lid is especially designed to avoid spillage of the contents of the cup through the drinking hole and the air hole.
It has been discovered that the jiggling or unintended movement of the cup causes a wave to form on the surface of the liquid and to travel back and forth across the surface of the liquid crashing against the side walls of the cup. When the wave hits the side walls of the cup, it splashes out of the drinking hole or the air hole, when the air hole is positioned next to the side wall of the cup. Thus, it is the movement of the wave on the surface of the liquid in the cup and its crashing against the side walls of the cup that causes the splashing and the spillage of the liquid.
It has also been found that when the air hole is made small and positioned in the center of the lid that spillage or splashing due to the wave through the air hole does not occur. Furthermore, it has been found that if the air hole is made rather small compared to the drinking hole, that the air hole will still function to allow liquids to flow out of the drinking hole and air in through the air hole. Thus, in the present invention, the air hole is positioned in the center of the lid and made relatively small compared to the drinking hole. In other words, the drinking hole is much larger than the air hole.
To avoid spillage out of the drinking hole, a large expansion chamber is employed which is in fluid communication with the drinking hole and in fluid communication with the interior of the cup. The chamber has one or more inlets which are positioned in the bottom wall and/or the side wall of the chamber. The drinking hole is positioned in the top wall of the chamber. The drinking hole and the inlets of the chamber are not in vertical alignment with each other. Thus, when any portion of the wave comes through the inlets into the chamber, it does not go through the drinking hole, but rather, is redirected back into the cup or contained in the chamber. This prevents spillage of the contents of the cup through the drinking hole.
The chamber has a bottom portion which extends below the lid and down into the area which is formed by the cup. The top portion of the chamber can be either coplanar with the top surface of the lid or extend above the top surface of the lid.
Preferably, the chamber has an arched or crescent shape, when viewed from above. The arched chamber preferably extends both above and below the planar surface of the lid. The drinking hole is positioned in the top wall of the chamber. The bottom chamber portion extends below the planar surface of the lid and preferably contains one or more inlets through which the contents of the cup travel to reach the drinking hole. The arched chamber follows the curvature of the lid, is centered on the drinking hole, and is in fluid communication with the drinking hole. The arched chamber is formed along the edge of the lid and has one or more inlets to allow the liquid contents of the cup to travel into the chamber. The inlets can be in the bottom wall of the chamber, in the end walls of the chamber, or the side walls of the chamber. The drinking hole is positioned in the top wall of the chamber to allow the liquid contents to flow from the cup through the chamber and into the user""s mouth. The center line of the chamber (assuming the chamber is essentially cylindrical in cross section) follows a radial line from the center of the lid that is less than the radius of the lid and is concentric with the radius of the lid. The lid itself has an engaging periphery to allow it to engage the rim of the cup and become removably affixed to the rim of the cup. In this way, the lid of the present invention fits a conventional disposable cup and no special cup must be employed with the lid of the present invention.
It is preferred that the lid of the present invention be molded into a one-step molding process. For example, the lid assembly is suitably made by thermoforming. In this process, the lid is made up of two pieces, one piece which is a disc that makes up the majority of the lid and can generally be referred to as the top of the lid while the other piece is a bottom section which forms the bottom portion of the chamber. The bottom section of the lid can be rotatably connected to the disc or, alternatively, can be separate from the disc.
Broadly, the splash-proof lid assembly for making a splash-proof lid for a drinking cup in accordance with the present invention comprises:
a circular disc having a snap fitting periphery for engagement with a cup rim;
an air hole positioned in said disc at the center of said disc;
a drinking hole positioned in said disc adjacent said snap fitting periphery of said disc, said drinking hole being larger than said air hole;
a first engagement means positioned on said disc at the underside of said disc between said snap fitting periphery and said air hole;
a bottom lid section having an arcuate side which mates with a portion of said snap fitting periphery of said disc, and a second engagement means for engaging with said first engagement means when said arcuate side mates with said snap fitting periphery; and
a chamber formed between said disc and said bottom lid section when said bottom lid section is placed against the underside of said disc and said first engagement means engages said second engagement means and said arcuate side mates with said portion of said snap fitting periphery, said chamber having a bottom chamber portion which is formed by said bottom lid section and extends below said disc, said chamber being centered on said drinking hole, said disc forming a top chamber portion, said chamber having one or more inlets formed in the bottom chamber portion and said inlet not being in vertical alignment with said drinking hole.
Preferably, said bottom lid section is rotatably attached to said disc along said snap fitting periphery of said disc and said arcuate side of said bottom lid section. Said bottom lid section can also be separate from said disc until said bottom section is mated with said disc.
Preferably, the top chamber portion, which is formed in said disc, extends upwardly from the planar surface of said disc, and is centered on said bottom chamber portion, said drinking hole being centered in said top chamber portion.
The inlets in the bottom chamber portion are preferably in the side walls, the end walls, or the bottom of said bottom chamber portion.
In one embodiment, the top portion of said chamber is flat and coplanar with said disc.
More preferably, the chamber has an arcuate shape which is concentric with the snap fitting periphery of said disc.
Broadly, the splash-proof lid for a drinking cup in accordance with the present invention comprises:
a circular disc having a snap fitting periphery for engagement with a cup rim;
an air hole in said disc which is positioned in the center enter of said disc;
an arched chamber adjacent said snap fitting periphery, said chamber having a center line which follows a radial line that is concentric with the radius of said disc and less than the radius of said disc, said chamber having a top portion which extends above the top surface of said disc and a bottom portion which extends below the bottom surface of said disc;
a drinking hole in a top wall of said chamber, said chamber centered on said drinking hole, said air hole being smaller than said drinking hole; and
one or more inlets in said chamber positioned in said bottom portion of said chamber, such that said inlet is in fluid communication with said drinking hole to allow a user to drink through the lid when the lid is placed on top of a drinking cup.
Broadly, the splash-proof lid assembly for making a lid for a drinking cup in accordance with the present invention can be defined as comprising:
a circular disc having a periphery;
a first snap fitting periphery portion extending around a first portion of said periphery, said first snap fitting periphery portion absent from a second portion of said periphery;
a chamber top portion with a drinking hole therein, said chamber top portion positioned adjacent to said periphery at said second portion of said periphery, said chamber top portion rising above the top surface of said disc;
an air hole positioned in the center of said disc;
a bottom section having an arcuate side, said bottom section having a second snap fitting periphery portion adjacent said arcuate side, and a chamber bottom portion having one or more inlets therein, said chamber bottom portion adjacent said second snap fitting periphery portion,
said bottom section rotatably attached to said disc along said periphery of said disc such that when said bottom section is rotated under said disc said second snap fitting periphery portion is positioned in said second portion of said periphery, said chamber bottom portion aligns with said chamber top portion to form an arched chamber in said lid, said one or more inlets are in fluid communication with said drinking hole, and said first snap fitting periphery portion and said second snap fitting periphery portion align for a complete snap fitting periphery of said lid.
Preferably, the arched chamber forms an angle of about 5xc2x0 to about 90xc2x0 with respect to the radius of the lid. More preferably, the arched chamber forms an angle of about 15xc2x0 to about 75xc2x0 and most preferably the angle is about 30xc2x0 to about 60xc2x0.
The inlet may be any suitable shape. Most preferably the inlet is either circular or oval. It is most preferred to use two or more inlets in the chamber.
It is also preferred that the bottom wall of the chamber be inclined such that liquid in the chamber flows out of the chamber back into the cup through the inlets when the lid is horizontal.